From the March 2008 issue of Entrepreneur

What: Sleepwear and undergarments made from moisture-wicking fabric
Who: Lesley Hatfield of NiteSweatz
Where: Atlanta
When: Started in 2004
Startup Costs: $50,000

While working as a personal trainer in 2003, Lesley Hatfield, 37, came across her big idea when she noticed a female client struggling to keep up during a routine run. The woman complained she was tired because, suffering from menopausal night sweats, she had woken up three times the night before to change clothes.

"Off the cuff, I said, 'Why don't you try sleeping in your running clothes?'" recalls Hatfield. "That was the 'aha' moment."

Hatfield soon realized there were no sleepwear companies making pajamas with the same moisture-wicking technology used in workout clothes--and she decided to take advantage of the idea herself. "I knew how technology had revolutionized exercise--no one works out in plain old cotton T-shirts anymore--and I felt this type of fabrication would be ideal for women suffering from night sweats," explains Hatfield, an exercise physiologist for 11 years.

Striving to make her products functional yet fashionable, Hatfield looked to the closets of trendy relatives and clients for her research. "I asked every woman I knew what she liked and disliked about her pajamas and began to create styles that would appeal to these ladies," she says.

NiteSweatz hit stores in 2004, and although it was originally intended for menopausal baby boomers, the line of soft and feminine lace camisoles, tank tops and sleeping gowns soon became attractive to women of all ages.

With last year's sales closing in on $1 million, Hatfield envisions the company becoming a household name and an international brand in the next five years--and encourages entrepreneurial hopefuls to take risks to find success. "So many great ideas [are] never acted on because of fear," she says. "If you have an idea, if it wakes you up at night, then you have a responsibility to yourself to act on it."